1. Field of the Invention
The present invention relates to a fitting jig of an endoscope hood member used to fit the hood member at an end portion of an inserted portion of an endoscope.
2. Description of the Related Art
A conventional example of an endoscope apparatus for use in an operation is formed by disposing an objective lens, a light guide, an air and water supply port, and a suction port in an end portion of an inserted portion of an endoscope. Such an endoscope apparatus irradiates a subject such as living tissue with light from the light guide and allows the lighted subject to be viewed via the objective lens so as to suck, through the suction port, air, water, or other material fed through the air and water supply port.
In this regard, when an attempt is made to insert the endoscope into, for example, the stomach, the mucous membrane of the stomach often contacts with and covers the objective lens provided in the end portion of the inserted portion of the endoscope. Thus, more inner areas of the stomach can no longer be viewed.
Correspondingly, Jpn. Pat. Appln. KOKAI Publication No. 11-206702 discloses an end structure of an endoscope in which the end portion of the inserted portion of the endoscope is provided with a guide portion to prevent the mucous membrane from covering the objective lens to block the view. The guide portion of the end structure of the endoscope is a hood-like member having an inner peripheral surface gradually widened so as to draw a curve starting from an end surface of its end portion.
It is assumed that with an endoscope apparatus formed so that a hood member can be freely installed on and removed from an end portion of an endoscope, when the hood member is installed in the end portion of the endoscope, the end portion is insufficiently pressed into the hood member. Then, the hood member projects further from its regular position to cause a larger part of the hood member to come into view. Conversely, if the hood member is installed so that the hood member does not project enough to reach its regular position, the hood member becomes less effective.
Further, with the endoscope apparatus formed so that the hood member can be freely installed on and removed from the end portion of the endoscope, if the hood member is shaped to fit the view, it may be installed at a position different from its regular position in a rotating direction. Consequently, a larger part of the hood member comes into view.